Picker stick buffer for looms



1961 J. G. WILLIAMSON, JR 3,004,563

PICKER STICK BUFFER FOR LOOMS Filed Aug. 15, 1960 United States Patent Ofiice 3,004,563 Patented Oct. 17., 1961 3,004,563 PICKiER STICK BUFFER FOR LooMs John G. Williamson, In,

Charlotte, N.C., assignor to 4 Perfecting Service Company, Charlotte, N.C., a corv p'oratron of North Carolina Filed Aug. 15, 1960, Ser. No. 49,556 7 Claims. (Cl. 139-166) looms, and more especially,

provideadequate cushioning or butting action, such prior devices have had to utilize pliable straps formed of many layers of pliable material or they have had to be excessively thick, and thus have been an expensive part of a loom. Further, such prior buffer straps have been subjected to excessive bending stresses which would not only result in the straps becoming excessively worn or cracked a relatively short period of use, but the yieldability thereof would decrease from the time the picker stick engaged the same until the picker stick was stopped in the course of each active stroke thereof.

It is an object of this invention to provide an improved picker stick buffer including a support for the buifer strap, which support is so formed that those portions of the strap which are laterally opposed with respect to the path of travel of the picker stick are bowed generally toward the picker stick so that the laterally opposed loop portions of the strap are caused-to bend about a relatively large radius upon impact of the picker stick thereagainst as compared to straps supported according to prior known devices. By causingthe strap to reactin this manner, the resistance of the strapto the movement of the picker stick gradually increases during the bufiing action, as opposed to the resistance etfected by bufling straps of prior butling devices.

. It is a more specific object of this invention to provide a picker stick buffer of the character describedwherein the support for the buffer strap comprises a body having a relatively broad fiat surface against which corresponding inner end portions of the strap are clampingly secured and wherein opposed ends of the body are provided with outwardly projecting ribs thereon which engage laterally opposed portions of the strap at the points at which the strap bends away from the substantially flat face of the body. Thus, the opposed ribs maintain the strap in a more elliptical shape from the time of engagement thereof by the picker stick until the picker stick has stopped its movement, as compared to the buffer straps of prior known devices.

It is another object of this invention to provide a picker stick butter of the character described wherein said substantially flat outer face of the support is provided with serrations thereon to assist in maintaining the strap in the desired clamped position. i

' of picker stick 13 loosely extends.

Some of the objects of the invention having been the picker stick at the end of an active shuttle-throwing stroke thereof;

FIGURE 3 is an exploded isometric view of the improved picked stick butfer removed from the loom, with parts broken away for purposes of clarity;

FIGURE 4 is a sectional plan view of the improved picker stick buflier taken substantially along line 44 in FIGURE 1;

FIGURE 5 is a sectional plan view similar to FIG- URE 4, but showing a prior art type of picker stick butter for purposes of comparison with the picker stick buffer of the present invention.

Referring more specifically to the drawing, the improved picker stick butter, broadly designated at 10, is mounted on a bracket 11 suitably attached to or integral with the frame 12 of the loom, only one side of a portion of the loom being shown in FIGURES 1 and 2. The lower end of a picker stick 13 is mounted on the lower portion of the loom in a manner well known in the art, and the picker stick 13 is moved inwardly in an active stroke by a lug strap 14 through which a medial portion The upper portion of picker stick 13 extends through the usual slot provided in an oscillatable lay 15 and has a picker 16 mounted on the upper end thereof for engagement with a shuttle 17. With the exception of the improved picker stick buffer 10, the parts of the loom heretofore described are conventional and their operation is well known in the art. Accordingly, a further detailed description of the loom is deemed unnecessary.

The improved picker stick bufier comprises a looped buffer strap 20 of pliable or yieldable material, and which may be made from one or more plies of leather, fabric, natural or synthetic rubber, or other suit-able pliable-web material. Strap 20 is shown as being doubleended, but may be in the form of an endless strap, if desired. The bufier strap 20 is clampingly attached to the loom by a support 21, a clamping plate 22 and a screw 23.

Screw 23 loosely penetrates clamping plate 22 and support 21 and may be threaded into bracket 11 or may 'have a nut 24 mounted thereon as shown in FIGURE 4. The proximal faces 25, 26 of support 21 and clamping plate 22 are substantially fiat or planar and are preferably provided with respective substantially vertical serrations which engage opposed surfaces of the inner portion or proximal ends of the strap 20 to assist in maintaining Strap 20 in lateral position with respect to picker stick 13 when the strap is clamped between the proximal surfaces 25, 26 of support 21 and clamping plate 22.

In order to further assist in maintaining the butter strap 20 in lateral position relative to the picker stick 13, the upper and lower portions of support 25 are preferably provided with respective horizontal outwardly projecting ribs 30, 31 whose proximal surfaces are spaced apart a distance substantially equal to the width or vertical height of the inner portion or opposed end portions of buffer strap 20.

It has been found that, in order that the strap 20 has an eflicient bufling or cushioning action and relatively long useful life, it is necessary that the strap is normally maintained substantially elliptically shaped with its longitudinal axis A (FIGURE 4) substantially positioned in alinement with and parallel to the path of movement of the picker stick 13, and with its lateral axis B extending in a horizontal plane at a substantially right angle to the path of travel of picker stick 13,. while maintaining the laterally opposed side portions of the boiler strap 20 (in alinernent with the lateral axis 'B thereof) sufiiciently outwardly bowed or outwardly convex to insure that said opposed side portions of the buffer strap 20 will spread apart upon impact of the picker stick 13 against the end smegma portion of the check strap loop opposite from the support 21. On the other hand, it is desirable that the curvature of laterally opposed side portions of the butter strap defined, by the laterahaxisB. normally have-larger radii than the radius of that portion of the. buffer strap- Which is to betengagedby the picker stick 13;-

By maintainingsuchnormal configuration: of the butter strap 20, the amount ofresistance to movement of the picker stick 13, from: the instant it engages the. outer. surface. ofthe butter strap- 20 until it comesto:rest-,.ren1ains substantially constant or is gradually increased to? an $X-' tent depending upon the characteristics of the: material of which the buffer strap 20' is made.

Now, in; order to maintain. the desired normals configuration of the butter strap 20 when itis ,not engaged by the picker stick 1 3, opposed sides of the. support 21 are provided with outwardly projecting abutments- 32,. 33 which project in substantially right-angular relation. from the main planar face 25 adistance substantially equal to'the thickness ofthe bufifer strap, 20. .Abutrnents 32, 33 may be in the form .of ribswhich are preferably rounded, as.-shown-,-. and whichare. spaced: from respective side. edges of the. clamping; plate 22 sufliciently so as. to upset. and thereby produce a relatively sharp'bendlinthe' bufferstrap, as at 34,. and to thereby applylaterally inward pressure to opposed sideportions of buffer strap. 20and to force outwardly the opposed side portions of strap 20 generally parallel to the-path of thepicker stick 13.. It. has been found desirable to. spacethe proximal surface of each abutment 32, 33 from the respective sideedge ofclamping-plate 22 a distance-substantially equalto: the. thickness of the butter. strap-20..

This causes the bufler strap 20 to. normally occupy the: normal configuration above setforth. Thus, it will be noted in FIGURE 4 that,. as picker stick 13 rnoves ins wardly in engagementwith. buffer strap 20- toward clampingplate 22, the. pressure exerted: against opposed side: portions of the buffer strap 20 by the abutments32, 331 yieldably opposes lateral outward movement of,.oppsed side portions of butter. strap 20, withthe result that, as. picker stick 13 moves to the broken line position of FIG- URE 4, or from the position of FIGURE 1 to that of FIGURE 2, the gradually reducing. radii of opposed. side portions of buffer strap 20. yieldably resistsiinward move ment of the outer central portion of-the. buffer strap..20,t thus,.bringing the picker stick 13 to asmoothstopwithout subjecting the picker stickito a-sudden shock- By way of comparison, a prior art type ofpicker. sticlc buffer is shown in FIGURE 5, wherein thoseparts which. correspond to. the parts of- FIGURE 4 shall' bear. the same reference characters with theprime. notation added. In FIGURE 5, it willbe noted that. the supportzl. is devoid of any means whatsoever forv applying pressureto opposed side portions of the butter strap 20. Accordingly, the butter strap 20 normally occupies a. position such.

that opposed side portions ,thereofiare bowed outwardly and are more acutely curved than the portion ofthe-strap;-

which is engaged by the picker stick 13.'-.

Accordingly, as the picker stick 13 moves'into'engage' ment with the outer surface" of strap 20-. and subsequently moves the outer portion of buffer strap 20 inwardlyto" substantially'th'e' broken line position ofFIGUR E 5'; it will be notedthatopposed sideportions-pf thebutfer strap are curvedquite' sharply as compared to -opposed side portions of the buffe'r strap=20"of FIGURE 4, so-tha't the outer surface of the butter strap 20' becomes cracked and worn quite easil'y, andthere is very little resistance to the inward movement of the picker stick 13' as .it cn-;

gages the very nearly flat central portion of'jthe buffer. strap 20'. It will be noted that. the picker stick 1'31. hows the outer portion. of the. bufier strap 20. inwardly. to a considerably greater extent than the. extent 'to which the bulfer strap 20 of FIGURE 4- is bowed inwardly by;

the picker stick13 when both: of-the picker sticks-13; 13'- 4 engage the outer portionsof the respective buffer straps 20, 20' under substantially the same amount of force.

From the foregoing, it is apparent that applicants novel mounting for the buffer strap 20 will maintain greater potential resistancetto inward movement of the outer portionofi thebuflerstrap Nth-an the support 215 willmaint'aimin'tBeputerpprtiOniOf the buffer strap 20'. lhtrther; since the abutment'sdf; 33 maintain. a. greater strength inlthelzouter portiontofthe. loop. ollthe buffer strap 20, it followsthatwthezabutments '32, 33 of FIG- URE 4 also maintain the opposed side portions of the loop formed. oft; hutfer'strap'. 20 atlarger radii than the opposed side portions of thebuffer' strap; 20 'inFIGURE 5; with: the' resuzlt. that thebufierstrap 20 will have a much longerru'sefuh life thansthei-butfer strap 20', assum ingI-th'at the'butierstraps'ztl izo are made of substantial.- ly the same materiali'and areof substantiallythe samewidth-and thickness;

In the drawings and specification there has been: set forth: a preferred embodiment of the invention and, al-' though specific term's are employed, they are used in a generic and descriptive sense only and 'not for purposes of limitation=,-th'e .scope of'tlie invention being d'efined intheolbiihs.

1'-.'- A butter for stoppinginward movement ofa picker stielc of a'-:.loom*, comprising a rigid support-having; a'

' substantially planar surface facing 'the pick'erstick, a-

buffer strap in inep -form having a portion attached .to' and extending throughout-substantially the length of said planar surfacaand laterallyof the path of the-- picker stick; abutment means projecting 'outwardly from laterally oppose'cf ends-ofsaiif surface'and'toward the picker stick, and abutment m'eansengaging outer surfaces of opposed side portions oli-said loop and serving to upsetrespective portions oftlie'strap engaged thereby to maintain laterally opposcd'side portions of theloopat a pre' determined curvature:

2. In a l'oonr having'a picker stick, and means for imparting activeinward strokes to the picker stick; the combination of 'azbufier for th'eimpa'ctof :the picker stick atthe"; end of" each active stroke thereof comprising a loopedbuffer'strap; as'upp'ort' having alaterally extending planar surface positionedinwardly ofsaid picker stick, means securingan inner portion of'said'strap along said planar surface, and spaced means carried by said support and" applying pressure t'o' spacedside portions of the strap'at-"i'ts-outer'surface and adjacent laterally opposed ends =of sa'id-planar surface-in such amanner as to normal-ly-maintaih 'saitfstrap a substantially elliptical shape with, its lb'ngitudinali axis extending: substantially parallel: withtlie patlizofftravcliofi the pickerstick.

3. The: combination with 3.1100111 having'a picker stick, of: arbuflenfor thezimpact of the: picker stick comprising airigidzsuppottshavingiaasubstantially planar outer surface extending: laterall'yi of the. path; of: the picker stick, a. pliable butter: strap -ins-loop form means clampingly securing a portion of said strap, against and alongsaid planar surfiace,--andi-abutmenLmeans-carried by said: support and projecting; outwardlytherefrom substantially astraddle the clamping rneans and produeinga. sharp bend in. the buffer straps at ,eachipoiiit at -wliicl'1..the butf'er strap extends. outwardly from said" planar surface, said abutment means serving to maintain said 'loop in elliptical form with 1t8 longitudinal extending substantially parallel 'to-the path of travelof said picker stick.

4.- Thecombinationwitlraloonr having a picker stic Of a buffer for the impact of the picker stick' compnsrng a-rigid support=liaving=a first substantially planar outer sm-faceextending 1aterally-of tire pathzofthe picker-stick, a clamping: plate-having: arseeondplanar surface of-a ngtln'sub'stantialiyitheesamm as 'thealen'gth ot saidfiF- named planar surface airpliablerbnfierstr'ap in: 1 form haviflgifl portlsia .p sitionedibetweenthe-first and: second planar surfaces, means clampingly securing the clamping plate and the buffer strap to said support, and abutment means carried by said support and projecting outwardly therefrom substantially astraddle the clamping plate and producing a sharp bend in the buifer strap at each point at which the buffer strap extends outwardly from the first planar surface, said abutment means serving to maintain laterally opposed side portions of the loop at a substantially larger curvature than that portion of the loop remote from said support 5. A structure according to claim 4 wherein said abutment means comprises a pair of ribs extending substantially vertically along laterally opposed side edges of said support and engaging the outer surfaces of laterally opposed side portions of said strap.

6. A buffer for stopping inward movement of a picker stick of a loom, comprising a rigid support having a substantially planar surface facing the picker stick, a bufier strap in loop form having a portion extending throughout substantially the length of said planar surface and laterally of the path of the picker stick, a clamping plate secured to said support and clamping said portion of the strap to said planar surface, abutment means projecting outwardly from laterally opposed side edges of said support and toward the picker stick, said abutment means being spaced astraddle said plate sufiiciently to accommodate the strap between the abutment means and opposed side edges of said clamping plate, and said abutment means engaging the outer surface of said strap so as to upset respective portions of the strap engaged thereby and to maintain opposed side portions of the loop at a predetermined curvature.

7. For use in supporting a buffer strap for cushioning the impact of a picker stick of a loom; a rigid support having a planar surface for receiving a portion of the strap thereagainst, abutment means on said support projecting outwardly from opposed ends of said planar surface in substantially right-angular relation thereto, a clamping plate adapted to be secured in fixed relation to said planar surface and also being adapted to engage the surface of said strap opposite from the surface thereof received against said planar surface, and said plate having opposed end edges which are spaced apart a distance substantially equal to the distance between said abutment means.

References Cited in the tile of this patent UNITED STATES PATENTS 2,532,543 Dodenhoif Dec. 5, 1950 2,616,454 Ahlstrand Nov. 4, 1952 2,884,961 Plante et al. May 5, 1959 

